As is well known, spray nozzles of this type are used to cool a cast strand during casting. One strives here for the most even cooling effect possible in order to prevent cracks from being able to occur in the hot cast strand during the cooling process. Hence the efforts to design the spray nozzle such that the cooling jet delivered is structurally homogeneous. However, the respectively required cooling effect is different from case to case, both for technical reasons and due to the dimensions and/or the geometry of the format to be cast. For this reason the conditions of use of the spray nozzle are variable with regard to the air and/or water pressure and the air and/or water flow.
It is a disadvantage of the previously known spray nozzles of this type that in the latter both sizes influence one another during operation. This leads to uneven subjection of the cast strand to water drop accumulations that form here and there and which have an adverse effect locally upon the cooling effect of the jet of spray to an inadmissible extent.
A spray nozzle arrangement of this type is disclosed by EP-0 161 307. This consists of a pre-atomizing head and a nozzle mouth piece with its own mixing chamber that is provided with a delivery opening for narrow fan-shaped spray patterns. The sense and purpose of the arrangement is to generate with such spray patterns a spray jet that has a high degree of atomization and that contains liquid droplets of uniform size over the entire length and width. The problems deriving from the influence of the air and water pressure or the air and water flow upon one another are not resolved satisfactorily.